//////package mysql;
//////
//////public class mysql {
//////}
//////
//////Enter password: *********
//////Welcome to the MySQL monitor.  Commands end with ; or \g.
//////Your MySQL connection id is 8
//////Server version: 8.0.39 MySQL Community Server - GPL
//////
//////Copyright (c) 2000, 2024, Oracle and/or its affiliates.
//////
//////Oracle is a registered trademark of Oracle Corporation and/or its
//////affiliates. Other names may be trademarks of their respective
//////owners.
//////
//////        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
//////
//////mysql> use java113'
//////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''' at line 1
//////mysql> use java113;
//////Database changed
//////mysql> select @@global.transaction_isolation;
//////+--------------------------------+
//////        | @@global.transaction_isolation |
//////        +--------------------------------+
//////        | REPEATABLE-READ                |
//////        +--------------------------------+
//////        1 row in set (0.00 sec)
//////
//////mysql> set global transaction isolation level read uncommitted;
//////Query OK, 0 rows affected (0.00 sec)
//////
//////mysql>  select @@global.transaction_isolation;
//////+--------------------------------+
//////        | @@global.transaction_isolation |
//////        +--------------------------------+
//////        | READ-UNCOMMITTED               |
//////        +--------------------------------+
//////        1 row in set (0.00 sec)
//////
//////mysql> start transacion;
//////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'transacion' at line 1
//////mysql> start transaction;
//////Query OK, 0 rows affected (0.00 sec)
//////
//////mysql> select @@tx_isolation;
//////ERROR 1193 (HY000): Unknown system variable 'tx_isolation'
//////mysql>
//////
//////Enter password: *********
//////Welcome to the MySQL monitor.  Commands end with ; or \g.
//////Your MySQL connection id is 9
//////Server version: 8.0.39 MySQL Community Server - GPL
//////
//////Copyright (c) 2000, 2024, Oracle and/or its affiliates.
//////
//////Oracle is a registered trademark of Oracle Corporation and/or its
//////affiliates. Other names may be trademarks of their respective
//////owners.
//////
//////        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
//////
//////mysql> use java113;
//////Database changed
//////mysql>  select @@global.transaction_isolation;
//////+--------------------------------+
//////        | @@global.transaction_isolation |
//////        +--------------------------------+
//////        | REPEATABLE-READ                |
//////        +--------------------------------+
//////        1 row in set (0.00 sec)
//////
//////mysql>  select @@global.transaction_isolation;
//////+--------------------------------+
//////        | @@global.transaction_isolation |
//////        +--------------------------------+
//////        | READ-UNCOMMITTED               |
//////        +--------------------------------+
//////        1 row in set (0.00 sec)
//////
//////mysql> start transaction;
//////Query OK, 0 rows affected (0.00 sec)
//////
//////mysql> select @@tx_isolation;
//////ERROR 1193 (HY000): Unknown system variable 'tx_isolation'
//////mysql> select @@transaction_isolation;
//////+-------------------------+
//////        | @@transaction_isolation |
//////        +-------------------------+
//////        | REPEATABLE-READ         |
//////        +-------------------------+
//////        1 row in set (0.00 sec)
//////
//////mysql>
////
////Enter password: *********
////Welcome to the MySQL monitor.  Commands end with ; or \g.
////Your MySQL connection id is 18
////Server version: 8.0.39 MySQL Community Server - GPL
////
////Copyright (c) 2000, 2024, Oracle and/or its affiliates.
////
////Oracle is a registered trademark of Oracle Corporation and/or its
////affiliates. Other names may be trademarks of their respective
////owners.
////
////        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
////
////mysql> use java113;
////Database changed
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> set global transaction isolation level repeatable raed;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'raed' at line 1
////mysql> set global transaction isolation level repeatable read;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | REPEATABLE-READ                |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> set global transaction isolation level reada uncommitted;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'reada uncommitted' at line 1
////mysql> set global transaction isolation level read uncommitted;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> insert into account values (null, '赵六', 3000);
////Query OK, 1 row affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        | 16 | 赵六   |    3000 |
////        +----+--------+---------+
////        4 rows in set (0.00 sec)
////
////mysql> rollback;
////Query OK, 0 rows affected (0.01 sec)
////
////mysql> select @@global.transaction_isolation
////    -> ;
////            +--------------------------------+
////            | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> update account set balance = balance - 100 where name = '李四';
////Query OK, 1 row affected (0.00 sec)
////Rows matched: 1  Changed: 1  Warnings: 0
////
////mysql> update account set balance = balance + 100 where name = '张三';
////Query OK, 1 row affected (0.00 sec)
////Rows matched: 1  Changed: 1  Warnings: 0
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |    1000 |
////        |  2 | 李四   |     900 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> rollback;
////Query OK, 0 rows affected (0.01 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> insert into account values (null, '赵六', 100);
////Query OK, 1 row affected (0.00 sec)
////
////mysql> rollback;
////Query OK, 0 rows affected (0.01 sec)
////
////mysql> set global transaction isolation read committed;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'read committed' at line 1
////mysql> set global transaction isolation level read committed;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-COMMITTED                 |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transasction;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'transasction' at line 1
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> insert into account values (null, '赵六', 100);
////Query OK, 1 row affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        | 18 | 赵六   |     100 |
////        +----+--------+---------+
////        4 rows in set (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-COMMITTED                 |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> rollback;
////Query OK, 0 rows affected (0.01 sec)
////
////mysql>
////
////Enter password: *********
////Welcome to the MySQL monitor.  Commands end with ; or \g.
////Your MySQL connection id is 19
////Server version: 8.0.39 MySQL Community Server - GPL
////
////Copyright (c) 2000, 2024, Oracle and/or its affiliates.
////
////Oracle is a registered trademark of Oracle Corporation and/or its
////affiliates. Other names may be trademarks of their respective
////owners.
////
////        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
////
////mysql> use java113;
////Database changed
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | REPEATABLE-READ                |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        | 16 | 赵六   |    3000 |
////        +----+--------+---------+
////        4 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> commit;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-UNCOMMITTED               |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |    1000 |
////        |  2 | 李四   |     900 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> commit;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> start transacr+tion;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'transacr+tion' at line 1
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        | 17 | 赵六   |     100 |
////        +----+--------+---------+
////        4 rows in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> commit;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-COMMITTED                 |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> start transaction;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        | 18 | 赵六   |     100 |
////        +----+--------+---------+
////        4 rows in set (0.00 sec)
////
////mysql> seelct @@global.transaction_isolation;
////ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'seelct @@global.transaction_isolation' at line 1
////mysql> select @@global.transaction_isolation;
////+--------------------------------+
////        | @@global.transaction_isolation |
////        +--------------------------------+
////        | READ-COMMITTED                 |
////        +--------------------------------+
////        1 row in set (0.00 sec)
////
////mysql> select * from account;
////+----+--------+---------+
////        | id | name   | balance |
////        +----+--------+---------+
////        |  1 | 张三   |     900 |
////        |  2 | 李四   |    1000 |
////        | 10 | 王五   |    2000 |
////        +----+--------+---------+
////        3 rows in set (0.00 sec)
////
////mysql> commit;
////Query OK, 0 rows affected (0.00 sec)
////
////mysql>
//
//Enter password: *********
//Welcome to the MySQL monitor.  Commands end with ; or \g.
//Your MySQL connection id is 20
//Server version: 8.0.39 MySQL Community Server - GPL
//
//Copyright (c) 2000, 2024, Oracle and/or its affiliates.
//
//Oracle is a registered trademark of Oracle Corporation and/or its
//affiliates. Other names may be trademarks of their respective
//owners.
//
//        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
//
//mysql> select @@global.transaction_isolation;
//+--------------------------------+
//        | @@global.transaction_isolation |
//        +--------------------------------+
//        | READ-COMMITTED                 |
//        +--------------------------------+
//        1 row in set (0.00 sec)
//
//mysql> use java113;
//Database changed
//mysql> start transaction;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql> insert into account values (null, '赵六', 200);
//Query OK, 1 row affected (0.00 sec)
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |     900 |
//        |  2 | 李四   |    1000 |
//        | 10 | 王五   |    2000 |
//        | 19 | 赵六   |     200 |
//        +----+--------+---------+
//        4 rows in set (0.00 sec)
//
//mysql> update account set balance = balance - 100 where name = '李四';
//Query OK, 1 row affected (0.00 sec)
//Rows matched: 1  Changed: 1  Warnings: 0
//
//mysql> update account set balance = balance + 100 where name = '张三';
//Query OK, 1 row affected (0.00 sec)
//Rows matched: 1  Changed: 1  Warnings: 0
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |    1000 |
//        |  2 | 李四   |     900 |
//        | 10 | 王五   |    2000 |
//        | 19 | 赵六   |     200 |
//        +----+--------+---------+
//        4 rows in set (0.00 sec)
//
//mysql> commit;
//Query OK, 0 rows affected (0.01 sec)
//
//mysql> start transaction;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql> select * from accoount;
//ERROR 1146 (42S02): Table 'java113.accoount' doesn't exist
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |    1000 |
//        |  2 | 李四   |     900 |
//        | 10 | 王五   |    2000 |
//        | 19 | 赵六   |     200 |
//        +----+--------+---------+
//        4 rows in set (0.00 sec)
//
//mysql> commit;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql>
//
//Enter password: *********
//Welcome to the MySQL monitor.  Commands end with ; or \g.
//Your MySQL connection id is 21
//Server version: 8.0.39 MySQL Community Server - GPL
//
//Copyright (c) 2000, 2024, Oracle and/or its affiliates.
//
//Oracle is a registered trademark of Oracle Corporation and/or its
//affiliates. Other names may be trademarks of their respective
//owners.
//
//        Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
//
//mysql> select @@global.transaction_isolation;
//+--------------------------------+
//        | @@global.transaction_isolation |
//        +--------------------------------+
//        | READ-COMMITTED                 |
//        +--------------------------------+
//        1 row in set (0.00 sec)
//
//mysql> use java113;
//Database changed
//mysql> start transaction;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |     900 |
//        |  2 | 李四   |    1000 |
//        | 10 | 王五   |    2000 |
//        +----+--------+---------+
//        3 rows in set (0.00 sec)
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |     900 |
//        |  2 | 李四   |    1000 |
//        | 10 | 王五   |    2000 |
//        +----+--------+---------+
//        3 rows in set (0.00 sec)
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |    1000 |
//        |  2 | 李四   |     900 |
//        | 10 | 王五   |    2000 |
//        | 19 | 赵六   |     200 |
//        +----+--------+---------+
//        4 rows in set (0.00 sec)
//
//mysql> commit;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql> start transaction;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql> select * from account;
//+----+--------+---------+
//        | id | name   | balance |
//        +----+--------+---------+
//        |  1 | 张三   |    1000 |
//        |  2 | 李四   |     900 |
//        | 10 | 王五   |    2000 |
//        | 19 | 赵六   |     200 |
//        +----+--------+---------+
//        4 rows in set (0.00 sec)
//
//mysql> commit;
//Query OK, 0 rows affected (0.00 sec)
//
//mysql>